Boat hull and method of constucting the same

ABSTRACT

The construction of boat hulls from a plurality of plates is facilitated by welding spaced parallel reinforcing bars to one side of the plate, and then bending the plate only in the direction perpendicular to the bars. The plate is then braced in that bent position and assembled in the hull construction. In the completed hull, the reinforcing bars of one plate will be at an angle to the bars of other plates.

United States Patent Bennekers 1 July 24, 1973 [54] BOAT HULL AND METHOD OF [56] References Cited CONSTUCTING THE SAME UNITED STATES PATENTS [75] Inventor: Johan Barthus Bennekers,Zaandam, 3,447,503 6/1969 Myers 114/77 R Netherlands 3,568,300 3/1971 Zidell.... 114/65 R X 2,857,662 10/1958 Allen 29/449 Asslgnw lnduslrleele 1,826,728 10/1931 Camps 114/79 R Handelscombinatie, l'lOllflHd, 3,658,286 4/1972 Terai el al 114/79 W X Rotterdam, Netherlands Primary Examiner-Milton Buchler [22] Flled 1971 Assistant Examiner-E. R. Kazenske [21] Appl. No.: 137,463 Attorney-Young & Thompson [30] Foreign Application Priority Data 1 fb ll rl f l r f l e construction 0 oat u s rom a p ura ity o p ates Apr. 27, 1970 Netherlands 7006118 is facilitated y welding spaced parallel reinforcing bars to one side of the plate, and then bending the plate only [52] CL 114/79 EE 2 in the direction perpendicular to the bars. The plate is [51] Int Cl 3 3/1'8 then braced in that bent position and assembled in the [58] Fie'ld R 79 w hull construction. In the completed hull, the reinforcing bars of one plate will be at an angle to the bars of other plates.

2 Claims, 4 Drawing Figures PATENIEU 3. 747. 551

SHEH E U? 2 INVENTOR BY MF' MJ ATTORNEYS BOAT HULL AND METHOD OF CONSTUCTING THE SAME The present invention relates to boat hulls and methods of constructing the same, in which a skin is formed by plates which are connected together and that have frame members and transverse stiffening members, by dividing the skin into developed sections and forming sheets of plates corresponding to said sections and by subsequently connecting the sheets with the frame members and the transverse stiffening members and with each other.

In the past, this has been done by first arranging the frame members in a shipyard, according to a predetermined regular arrangement, and then bending the sheets of plates about the frame members and securing them to the frame members and to each other. The disadvantage of this known method is that despite the use of plates formed in accordance with developed sec tions, so that the plates need be bent in one direction only, the fitting of these plates and the curving of them around the frame structures is a complicated and time consuming procedure.

Therefore, an object of the present invention is to provide a method of constructing boat hulls, which will be relatively simple and inexpensive to practice, for the production of boat hulls in a minimum of time and with a suitably strong structure.

Another object of the present invention is the provision of a boat hull which will be simple and inexpensive to prefabricate in the form of modular units, easy to assemble, and rugged and durable in use.

Briefly, the present invention achieves these objects by first securing to the sheets of plates before these are bent, a plurality of straight parallel reinforcing members which form the frame members. The sheets are then bent to conform to the desired shape, by bending the sheets in one direction only, perpendicular to the frame members. T he frame members thus become generatrices of the bent sheets. Once the sheets are bent, stiffening members extending transversely of the reinforcing members are secured to the reinforcing members, whereupon the thus-formed rigid sheets of plates are connected with one another to form a boat hull.

By the practice of this invention, all the sheets of plates from which the hull is to be formed can be completely prefabricated in their proper form in a factory or other buiding; while the assembling of the sheets of plates to form the hull in the shipyard can also be effected in a simple and rapid manner. To this end, the reinforcing frame members in the boat hull constructed according to the present invention are straight and do not bend when the sheets are bent. Thus the frame members will not extend in a predetermined regular pattern but will extend at an angle to the frame members of others of the sheets.

According to another feature of the invention, the flat sheets of plates may advantageously be bent to the desired shape by their own weight, because the sheet has flexibility in one direction only, perpendicular to the reinforcing members, and hence will sag under its own weight in that direction. In any event, the bending process is preferably effected by placing the sheet on a pin bed, which is mold formed by pins that extend upwardly to various elevations.

These and other objects and features and advantages of the present invention will become apparent from a consideration of the following description, taken in connection with the accompanying drawings, in which:

FIG. l is a perspective view of .a flat sheet of plates with the reinforcing frame members secured thereto;

FIG. 2 is a view similar to FIG. 1 but showing the sheet in its curved condition;

FIG. 3 shows the sheet of FIG. 2 with transverse stiffening members secured thereto; and

FIG. 4 is a perspective view of a boat hull constructed according to the present invention.

Referring now to the drawings in greater detail, and first to FIG. 1 thereof, it will be seen that initially, a plate 1 is formed comprised of a number of flat metal sheets secured together by welding at weld seams 4. To the sheet 1 are secured by welding a number of parallel bulb irons 2, all of them extending parallel to each other in spaced relation and parallel to the generatrices of the developed surface to be followed by the sheet.

FIG. 2 shows the FIG. 1 sheet in its bent position, it being noted that the bend is in one direction only, per pendicular to the irons 2, so that the irons 2 do not bend but remain straight and parallel to each other. The sheet may advantageously be bent by placing it on a pin bed, in the position shown in FIG. 2, it being understood that the pin bed is comprised by a plurality of vertically adjustable pins extending to different heights, so that when the sheet rests on all or substantally all the pins, it will have the bent shape shown in FIG. 2. It will also be understood that, as the sheet 1 can bend in one direction only, it has more tendency to sag under its own weight than if the irons 2 were not present; and it is thus possible to bend the sheet to the FIG. 2 position under the weight of the sheet and its attachedirons, or alternatively to add further weights to the sheet to promote the bending thereof.

FIG. 3 shows the addition of transverse stiffening members 3 to the sheet bent as in FIG. 2, with the aid of temporary supporting means 5, the stiffening members extending transverse to the irons 2 so that the sheet is made rigid against further deformation thereby to retain the curve of FIG. 2. In this connection, the sheet can be removed from the pin bed and conveyed to the shipyard in order to be connected with the other sheets by welding along the edges. of the adjacent sheets, and by welding the ends of the bars 2 to each other, and by securing the stiffening members 3 to each other or to other support structure.

FlG. 4 shows the various sheets assembledin the form of a boat hull, from which it will be understood that not all the irons 2 extend in the same direction but rather that although all the irons 2 of a given sheet extend parallel to each other, the irons 2 of a given sheet may and ordinarily will extend to various angles to the irons 2 of the other sheets.

From a consideration of the foregoing disclosure, therefore, it will be evident that all of the initially recited objects of the invention have been achieved.

Although the present invention has been described and illustrated in connection Wlthlfl preferred embodiment, it is to be understood that modifications and variations may be resorted to without departing from the spirit of the invention, as those skilledin this art will readily understand. Such modifications and variations are considered to be within the purview and scope of the present invention as defined by the appended claims.

What is claimed is:

curing transverse stiffening members of said curvature to the bent sheet to maintain said curvature, and then connecting the sheets together to form a boat hull with the sheets fairing into each other and the reinforcing members of one sheet being disposed at an obtuse angle to the reinforcing members of an adjacent sheet.

2. A method as claimed in claim 1, and bending said sheets to said predetermined curvature on a pin bed. 

1. A method of constructing a boat hull comprising a skin formed of plates connected to each oTher and having reinforcing frame members and transverse stiffening members, comprising securing to the sheets while the sheets are in a flat condition a plurality of straight spaced parallel coplanar reinforcing members, thereafter bending the sheets by their own weight to a predetermined curvature in one direction only until said reinforcing members are no longer coplanar, said direction being perpendicular to said reinforcing members, securing transverse stiffening members of said curvature to the bent sheet to maintain said curvature, and then connecting the sheets together to form a boat hull with the sheets fairing into each other and the reinforcing members of one sheet being disposed at an obtuse angle to the reinforcing members of an adjacent sheet.
 2. A method as claimed in claim 1, and bending said sheets to said predetermined curvature on a pin bed. 